Русско-англо-русский юридический словарь

We believe in investing in our people, irrespective of age.

This service should be available to everybody, irrespective of whether they can afford it. (COBUILD Advanced English Dictionary)

We checked him out, Ms. Morrone, regardless of what you suggested at the preliminary hearing. (Lisa Scottoline RUNNING FROM THE LAW (2001))

You are perhaps more likely to hear "regardless" in connection with emotions or cognition (Regardless of her feelings, for example) and "irrespective" when there are no "thinking" parts (like in a physics experiement or something - The ball reached the bottom of the ramp in the same amount of time, irrespective of which gate it was started from).

Whatever you do, don't use irregardless. (EnglishForward)